Okay, my wife says I have a really bad habit of over analyzing so excuse me in advance.

Were the twins even real?

You never got a good view of them and I remember when you first see them they are far away on an island. I zoomed in and they moved pretty mechanically. When they say their goodbye, they seem to SLIDE out of view.

Maybe I just misinterpreted the entire story wrong, but by the end I thought that Ned was just trying to scare you away. It's already apparent that he is good with electronics, and you find the boombox in his camp later on in the game - not to mention the stripped ski-mobiles later in the game.

While it's true that Delilah tells you that they've been found, we never actually meet Delilah, and you overhear a conversation between her and another person - implying maybe she is keeping things from you.

As I wrote this I started to doubt my theory, but hey, what do you guys think?

Nah dude you're overthinking this way too much.

Forget your Scooby-Doo theory for a second, where in the world did you get the idea they were twins?

i just thought the in game character models were just not great. when you see ned early i thought it wasn't that great either, and made me glad i didn't physically meet delilah

also yeah i don't think they're twins at all

Haha, I think that threw me more than the actual theory put forth, weren't they just supposed to be friends? Maaaaaaaaaaybe sisters.

Anyways, It sounds like you might be over thinking it, notice how there is only one real character model in the entire game besides yourself and he hardly moved besides waving his hand at you. I think it came down to 'ahh don't put too much effort animating two blobs' more than anything.
Crazy theories are all part of the fun though. Soo hey, whatever, let your head canon run wild.

No they're real.

You don't see them because Campo Santo didn't put in any close up third person characters other than a dead body and the dude in the helicopter whose covered head to toe and has very few animations. That's not me taking a jab at Campo Santo - the game didn't really need animated characters to do what it did, but those girls are totally real.

If the girls weren't real, why was the boom box out there, where did their clothes come from, their tent, their beers and teen girl magazines?

You don't get a good look at Ned either do you? So is he also not real?

Also yeah, where did you get that they're twins?

Haha oh my goodness, well one point to my wife. Thanks guys.